Monday, February 15

The experimental Vought XF5U-1
"Flying Pancake" is an interesting shape and intriguing aircraft
for many. Kittyhawk’s 48th
scale kit has a fair few possibilities for those looking for something out
of the mainstream. Out Man Gary was onto this kit and has dry fitted the major
components in his review for you…

You just never know what's going to be next on the Kitty
Hawk Model release schedule. They certainly are jumping all over the place with
the subjects being offered, not that it's a bad thing mind you. I doubt the
XF5U-1 Flying Pancake will be one of their big sellers but for those of us who
like to try something a bit off the beaten track it's a welcome addition to the
KH line-up. In 1:48 the kit is still very small and with such a small parts
count will be a quick and simple build.

The contents of the box will be familiar to those who have
purchased a KH kit before:

4 x plastic sprues in KH standard light grey

1 x clear sprue containing the canopy & clear nose cone.

2 x decal sheets providing a total of 3 markings options.
The second sheet (Decal B) has had the intended 'Anime' artwork removed as it
seems that KH could not work out a licensing agreement in time.

1 x photo etch brass
fret containing seat belts.

1 x printed assembly/painting manual with black & white
instructions and full colour paint & markings. The afor mentioned 'Anime'
color scheme is part of the book but those pages have been glued shut.

The XF5U discoidal aircraft was an invention of Charles H.
Zimmerman, who conceived the design in the early 1930s. He won a 1933 National
Advisory Committee for Aeronautics (NACA) design competition with a disc-shaped
concept capable of flying at high speeds or hovering; NACA rejected further
development because they thought the design was "too advanced".

Zimmerman joined Chance Vought Aircraft in 1937, and there
was able to produce an electric powered model of his design, designated V-162,
flown by remote control in test situations, tethered in a hangar. The rear
fuselage was hinged to act as an elevator.

Zimmerman provided an original blueprint to the US Navy
(featuring no horizontal stabilisers) in March 1939. A month later, the Navy
asked NACA (which later became NASA) to investigate the proposal. In October
1939 manufacture by Chance Vought of a small scale model for wind tunnel
testing was approved. The design was referred to as V-173.

Call it what you may, "Flapjack",
"Saucer" or "Pancake", it had no official name, but
Vought's last propeller-driven fighter would certainly answer to
"weird."

The "flying saucer" which thousands of Americans
saw in the sky in 1943, near Stratford, Connecticut was no extra-terrestrial
visitor or mysterious UFO; it was Vought's Model V-173 making one of its 200 or
more test flights with Boone T. Guyton or Richard Burroughs or even, on occasion,
Charles Lindbergh, at the controls. This was one of the strangest looking
flying machines to take to the air since the early pioneering days, but was
actually a revolutionary new plane which was built as an experimental fighter.
The V -173 proved to be virtually stallproof. At no time would the plane ever
stall or spin during the tests, no matter how tight the turn. Maximum speed of
the craft was 138 mph and it could climb 5,000 feet in 7 minutes.

The specifications for the XF5 U-1 fighter were truly
exciting considering the performances being achieved by the typical 1942
fighter. With a pair of 1,600 hp Pratt & Whitney R-2000-7 air-cooled water
injected engines, the maximum speed was to be 460 mph while the landing speed
was to be as low as 20 mph. Projecting even further, a pair of gas turbines
could provide a speed of 550 mph while landing at near zero ground speed. With
the turbine powerplant, the XF5 U-1 would actually hover motionless in the air,
hanging under its props like a helicopter. The Navy ordered two all-metal
XF5U-1's as the V-173 flights proceeded. One was to be used for static testing
while the second would be used for flight evaluation.

Unfortunately, although the XF5U-1 was shipped to Muroc,
California, for tests, it never flew. The jet age made propeller-driven
fighters a thing of the past and the XF5U was scrapped by the Navy having never
left the ground.

Test Fit

To me, the fit of a kit is one of the most important aspects
in determining how well the manufacturer has done their job in engineering the
model. You can inspect the sprues, make educated guesses about how the kit will
go together but nothing beats actually cutting the parts off and testing them.
I am a big advocate of dry fitting (holding the parts together with tape rather
than glue) as it gives me a real sense of how the model should best be
assembled and which parts need extra attention.

The photos that follow show how the main components of the
kit fit together. Overall I found that the fit was pretty good (ie no warping
or major gaps that need to be dealt with). Some of the parts don't align very
well (I'm thinking the engine intakes on the wing leading edge) and will hence
need some brute force to hold them while gluing

Sprues

Sprues A & B
are dominated by the fuselage/wing upper and lower parts. Surrounding these
main parts are the rest of the airframe (such as it is) with the vertical and
horizontal tails and engine intake covers.

The level of detail is on par with Kitty Hawks previous
releases that I have either reviewed or built. There is no visible flash and
parts are connected with reasonably sized sprue join points making cutting
parts off that much simpler.

Probably some of the smallest parts found in the kit are for
the cockpit. As you can see here the parts are well moulded and should be easy
enough to remove and clean up during construction.

Kitty Hawk have added both raised and recessed rivet detail
to the surface of the model. This is very nicely done. My only concern lies
with how much of the raised detail will be lost when sanding around poor
fitting joints like the one we saw in the dry fit for the intake to wing join.
Rectangular engine access panels are also provided on the wing upper and lower
parts. Unfortunately, no interior engine detail is provided so unless you plan
to add you own P&W R-2000 engines these panels will be best left closed.

One of the more interesting features of the model is the
inclusion of the arresting hook (which is stowed on the top of the fuselage
rather than below it.) I'm not sure how accurate these parts are because I
could not find any actual photos of the two XF5U's with such a hook fitted but
there are Vought line drawings that show how the hook was designed to operate
so I my guess is that KH based the parts off these.

The recessed rivet detail on KH kits are normally a little
on the soft side for my liking. I usually take the time to go over the model
surface with my riveting tool and sharpen up each rivet (yes it takes a while
but it’s worth the effort when it comes time to do that panel wash later on).

At first glance you could be forgiven for thinking the XF5U
was powered by jet engines (which drove propellers). The air intakes (and the
under wing exhausts for that matter) give little or no hint that in fact buried
inside the wing are a pair of 1600hp Pratt & Whitney R-2000-7 air-cooled
radial engines.

This is the first KHM kit I have reviewed that has raised
rivets and they look well done. I'm a bit concerned that some of these will be
lost due to sanding especially around the engine access panels on both the top
and bottom of the wing. This is somewhat disappointing as I really don't see
the point of putting open access panels on a model if you aren't providing any
internal detail to go behind them.

Sprue C covers
the two main wheel wells, the tail wheel well, undercarriage doors and the distinctive
extension shafts for the propellers & spinners.

The unusual tailhook is moulded in a single piece. KH seem
to have refined their moulding techniques resulting in noticeably smaller sprue
attachment points on all parts.

I'm not sure what (if any) references KH used for areas like
the wheel well interiors but as I'm not super concerned about such things on a
model I believe that what they have provided looks convincing enough to my
eyes.

One area that needs some assembly is the propeller shafts.
Each side consists of 4 parts to make up the shaft body and spinner body.

The surface panel lines and rivet detail will benefit from
some sharpening (with a scriber or rivet tool) if you plan to apply a wash to
the surface detail after painting.

The propellers on the XF5U-1 were 'handed'. This means each
side rotated the opposite direction to the other. As a result, the propellers
themselves need to be oriented correctly on our model. KH have provided keyed
mounting holes on the spinners to ensure the props cannot be inserted the wrong
way round.

The main gear doors are fairly simple but adding some basic
detailing to the interior like this is always welcome as it adds interest to
the underside of the model.

Sprue D rounds
out all the plastic parts in the kit. On this sprue we have the cockpit
interior, the main undercarriage struts and wheels, the engine exhausts (again
which look way more like a jet exhaust) and finally the eight propellers.

The XF5U propeller blades were specially constructed of wood
and mounted in two vertical planes. Each propeller blade was articulated and
could tilt fore and aft of its connections on the shaft. This is similar to the
movements of the rotors on a helicopter, to which the XF5U-1 seemed a second cousin.
The propeller blades were black from the root with white stencilling, then
varnished mahogany with yellow tips. KH seems to do a reasonable job of
capturing the shape of the blades.

The exhausts on the XF5U look more like jet nozzles that
something you would expect from a piston powered combustion engine.
Nevertheless, Vought combined the exhausts from the radial engines and they
exited the aircraft interior on the underside of the fuselage.

The main undercarriage struts housed two main wheels per
side. These parts look to be well moulded with minimal clean necessary before
assembly and paint.

This clear period photo of the XF5U-1 affords us some useful
information for detailing our model. Note the rivet detail on the propeller
shafts and hubs as well as the hydraulic piping lines on the main
undercarriage.

The kit wheels look convincing enough with the exception of
the hubs. The XF5U main wheels look very similar to those used on the F4U
Corsair and unfortunately the hubs provided by KH bare little resemblance to
XF5U photos. I'd be inclined to discard the KH wheels and use some resin
replacements from an F4U kit.

The cockpit of the XF5U was simple enough. KH provide the
main instrument panel with raised detail and recessed instrument faces. A
single piece decal is provided for the main IP and with a generous application
of decal softening solution should settle down well over the raised plastic
detail.

Cockpit sidewalls have moulded on detail which is pretty
typical (and acceptable in my opinion) for 1:48 scale.

Sprue GP rounds out the plastic parts. The canopy and
windshield, nose cone and navigation lights are all contained on this small
sprue.

The clear parts all moulded well and clear of any blemishes.
No mould seam lines need to be removed here as the canopy shape does not
require them.

One thing I'm always more conscious of with clear parts are
the size and location of the sprue tree attachment points. Unlike normal
plastic parts that you can easily repair if the sprue separation goes awry,
clear parts are not so forgiving.

A small photo etch brass fret is included containing a set
of seat belts. These look to be adequate for the task.

Decals

The decals provided by KH are visually in register and offer
solid color saturation. I have only used KH kit decals once (on my MiG-25
build) and from memory they performed well enough. I really doubt that anyone
will be coming out with aftermarket decals from this subject (unless they do a
what if sheet).

The second sheet comes cut as shown here. As I understand
it, KH had originally intended to provide a fourth Japanese Anime inspired
what-if scheme but apparently the licensing details could not be agreed prior
to the kits release and this option was scrapped from the kit (and decal
sheet).

Colours and Markings

Kitty Hawk provide a total of 3 marking schemes in the kit.
Of these, only one attempts in any way to accurately depict the two airframes
built by Vought, one was to be used for static testing while the second would
be used for flight evaluation.

US Navy Midnight Blue
- reflects the overall paint scheme used on the two evaluation aircraft.

US Navy Silver - a
what-if natural metal scheme.

US Army, Uncle Sam
Want You - a "what-if" US patriotic scheme.

Assembly Instructions

The assembly instructions are provided in a 12-page stapled
booklet format. The instructions are printed clearly and are well engineered
with exploding schematics explaining the suggested assembly sequence of each
sub assembly.

Conclusion

So, here we have another interesting subject to add to the
rapidly growing KittyHawk stable. I doubt this model will appeal to many in the
mainstream modelling community but if the subject does interest or motivate you
then you should buy the KH kit with confidence that with a minimum of effort
(certainly compared to many of KH's earlier kits) you will be able to create an
accurate replica of one of the more unusual aviation experimental aircraft.